Dry cleaning process

ABSTRACT

A dry cleaning process for in-home dry cleaning comprising a dry cleaning step of contacting a laundry article stained with particulate soil with a dry cleaning composition wherein the liquor to cloth ratio (w/w) (LCR) is at most 20, and wherein said composition comprises a) a non-flammable, non-chlorine containing organic dry cleaning solvent; b) a cleaning effective amount an acid surfactant.

The present invention relates to a dry cleaning process for laundryarticles.

Laundry articles can be cleaned using water as the primary medium withsurfactants and other cleaning agents. However, not all laundry articlescan be cleaned using water. These articles are cleaned in a dry cleaningprocess wherein an organic dry cleaning solvent is used as the primarymedium. In dry cleaning usually the laundry articles are immersed in orwashed with solvent liquids. Applications involving one or more stagesof immersion, rinsing and/or drying are known. Solvents can be used atambient temperature or at elevated temperatures up to the boiling pointof the solvent.

Many alternative solvents have been proposed to replaceperchloroethylene. Liquid carbondioxide is one example, but the highpressure equipment needed for this inorganic dry cleaning solvent makesit unpractical and prohibitively expensive. A novel and more promisingclass of dry cleaning solvents are the so called non-flammable,non-chlorine containing organic dry cleaning solvents. Examples mayinclude hydrofluoroethers such as nonafluoromethoxybutane andnonafluoroethoxybutane or hydrofluorocarbons as decafluoropentane.Hydrofluoroethers are relatively low in toxicity, are claimed to havezero ozone depletion potential, have relatively short atmosphericlifetimes, and can have very low global warming potentials relative tochlorofluorocarbons and many chlorofluorocarbon substitutes.Furthermore, HFEs are listed as non-volatile organic compounds by theEPA, and as such are not considered as smog precursors.

WO 00/36206 discloses a dry cleaning composition comprisinghydrofluoroether, 1-30 wt. % of a nonionic fluorosurfactant and lessthan 1 wt. % water. JP 11140499 discloses a dry cleaning compositioncomprising hydrofluoroether, 0 percent water and 10 and up to 90 wt. %of salt of a fluoralkyl phosphate surfactant. U.S. Pat. No. 6,127,430discloses a composition comprising from 0.1 to 99 parts by weight ofhydrofluoroether and from 99.9 to 1 parts by weight of water, the sum ofa and b equalling 100 parts, and certain fluorinated surfactants. WO97/22683 (3M) discloses a dry cleaning composition comprisinghydrofluoroether and 0.1 wt. % of a nonionic surfactant like fluoralkylsulphon amide. U.S. Pat. No. 5,610,128 discloses compositions withperfluoroalkylamine salts of octylphenyl acid phosphate.

However, this new class of non-flammable, non-chlorine containingorganic dry cleaning solvents has major drawbacks. These solvents areoften relatively poor solvents and show little or no cleaning activityon domestically stained and soiled laundry. In the absence of in-homedry cleaning, the known dry cleaning processes have been optimised fordry cleaning in an industrial setting which require large volumes of drycleaning solvent and correspondingly large dry cleaning machines. Thesedry cleaning processes have been optimised to aggressively clean toughindustrial stains with little garment care benefits. The large scale ofthe known dry cleaning process are less suitable for in-home drycleaning and other non-industrial purposes. Furthermore, theconventional dry cleaning of laundry is carried out in specialisedbusinesses. It requires expert knowledge of how to pretreat certainstains, how to treat certain fabrics. It includes labour and timeintensive post treatment steps such as pressing and ironing. Forexample, particulate soil is a common domestic stain that is difficultto clean using dry cleaning only without extensive manual pretreatment.Redeposition of soil often represents another problem in dry cleaningwhich may cause greying of laundry.

The present invention seeks to address one or more of the drawbacksmentioned above

Surprisingly, according to one aspect of the invention a dry cleaningprocess is provided for in-home dry cleaning comprising a dry cleaningstep of contacting a laundry article stained with particulate soil witha dry cleaning composition wherein the liquor to cloth ratio (w/w) (LCR)is at most 20, and

-   wherein said composition comprises-   a) a non-flammable, non-chlorine containing organic dry cleaning    solvent;-   b) a cleaning effective amount an acid surfactant.    The process according to this aspect of the invention—inter    alia—shows surprisingly effective stabilisation of particulate soil    to prevent redeposition of soil on laundry articles and greying    thereof, even in the absence of any specific pretreatment.

Garment care including minimising or avoiding wrinkles is a significantbenefit since this would reduce the need for time and energy consumingironing of the laundry articles. In addition, the present invention isparticularly suitable for an in-home dry cleaning application because itis possible to use very low volumes of organic dry cleaning solvent(liquid to cloth ratio) and still obtain effective cleaning and/orgarment care. Because low volumes of organic dry cleaning solvent areused, the dry cleaning process is highly suitable for non-industrialapplication since it can be carried out in a relatively small and costeffective dry cleaning apparatus.

These and other aspects, features and advantages will become apparent tothose of ordinary skill in the art from a reading of the followingdetailed description and the appended claims. For the avoidance ofdoubt, any feature of one aspect of the present invention may beutilised in any other aspect of the invention. It is noted that theexamples given in the description below are intended to clarify theinvention and are not intended to limit the invention to those examplesper se. Other than in the experimental examples, or where otherwiseindicated, all numbers expressing quantities of ingredients or reactionconditions used herein are to be understood as modified in all instancesby the term “about”. Similarly, all percentages are weight/weightpercentages of the total composition unless otherwise indicated.Numerical ranges expressed in the format “from x to y” are understood toinclude x and y. When for a specific feature multiple preferred rangesare described in the format “from x to y”, it is understood that allranges combining the different endpoints are also contemplated. Wherethe term “comprising” is used in the specification or claims, it is notintended to exclude any terms, steps or features not specificallyrecited. All temperatures are in degrees Celsius (° C.) unless otherwisespecified. All measurements are in SI units unless otherwise specified.All documents cited are in relevant part, incorporated herein byreference.

DETAILED DESCRIPTION OF THE INVENTION

Definitions

The term “dry cleaning process” used herein is intended to mean anyprocess wherein laundry articles are contacted with a dry cleaningcomposition within a closable vessel. However, as used herein this termdoes not include any process comprising steps wherein the laundryarticles are also immersed and rinsed in an aqueous cleaning compositioncomprising more than 80 wt. % water because this would damage garmentsthat can only be dry cleaned.

The term “dry cleaning composition” as used herein is intended to meanthe composition used in the dry cleaning process including the drycleaning solvent, any surfactant, cleaning agents but excluding thelaundry articles that are to be cleaned.

The term “organic dry cleaning solvent” as used herein is intended tomean any non-aqueous solvent that preferably has a liquid phase at 20°C. and standard pressure. The term organic has its usual meaning, i.e.,a compound with at least one carbon hydrogen bond.

When referring to the “weight of the cloth”, it is intended to mean theweight of the cloth of the laundry article after the cloth has beenequilibrated at 20° C., a relative humidity of 55% and standardpressure.

The term “laundry article” as used herein is typically a garment but mayinclude any textile article. Textile articles include—but are notlimited to—those made from natural fibres such as cotton, wool, linen,hemp, silk and man made fibres such as nylon, viscose, acetate,polyester, polyamide, polypropylene elastomer, natural or syntheticleather, natural or synthetic fur and mixtures thereof.

The term “liquid to cloth ratio” (w/w) (LCR) as used herein is intendedto mean the ratio of the weight of the total amount of dry cleaningcomposition to the weight of the cloth as defined above.

The term “immerse” as used herein is intended to mean that the laundryarticle is contacted with a cleaning effective amount of dry cleaningcomposition in a step of the dry cleaning process to wet the laundryarticle which is usually a LCR of greater than 0.5 or more preferably aLCR as given below. The term “cleaning effective amount” as definedherein is intended to mean an amount effective to obtain the desiredcleaning.

The term “in-home” as defined herein is intended to mean that the LCR ofthe dry cleaning step is at most 20. Although, the in-home dry cleaningis especially suitable for domestic homes, in some cases these smallappliances may also be used in hotels, airports on a non-industrialscale.

The water content refers to water purposefully added to the laundryarticles, for example as part of the dry cleaning composition as such ora pretreatment composition, including hydrated water as part ofingredients making up these compositions. It is not intended to includethe moisture of the untreated wash load e.g., a wet towel.

Dry Cleaning Process

According to a first aspect of the invention, a dry cleaning process isprovided for in-home dry cleaning comprising a dry cleaning step ofcontacting a laundry article stained with particulate soil with a drycleaning composition wherein the liquor to cloth ratio (w/w) (LCR) is atmost 20, and wherein said composition comprises

-   a) a non-flammable, non-chlorine containing organic dry cleaning    solvent;-   b) a cleaning effective amount an acid surfactant.

In one preferred embodiment the dry cleaning step is a low aqueous drycleaning step and said composition is a low aqueous dry cleaningcomposition comprising 0.01 to 10 wt. % of water.

According to yet another aspect of the invention, one preferred drycleaning process further comprises a non-aqueous dry cleaning stepwherein the laundry article contacted with a non-aqueous dry cleaningcomposition, said non-aqueous dry cleaning composition comprising

-   0.001 to 10 wt. % of a surfactant;-   0 to 0.01 wt. % of water;-   0 to 50 wt. % of a cosolvent and-   a non-flammable, non-chlorine containing organic dry cleaning    solvent.

According to another aspect of the invention a sequential dry cleaningprocess is provided comprising:

-   a) a non-aqueous dry cleaning step, wherein said articles are    contacted with a non-aqueous dry cleaning composition said    non-aqueous dry cleaning composition comprising-   0.001 to 10 wt. % of a surfactant;-   0 to 0.01 wt. % of water;-   0 to 50 wt. % of a cosolvent and-   a non-flammable, non-chlorine containing organic dry cleaning    solvent;-   b) at least one low-aqueous dry cleaning step, wherein said articles    are contacted with a low aqueous dry cleaning composition said low    aqueous dry cleaning composition comprising-   0.001 to 10 wt. % of a cleaning effective amount an acid surfactant;-   0.01 to 50 wt. % of water;-   0 to 50 wt. % of a cosolvent; and-   a non-flammable, non-chlorine containing organic dry cleaning    solvent;-   and, optionally, at least one rinsing step, wherein the articles are    contacted with a rinse composition said rinse composition comprising-   0 to 0.0001 wt. % of a surfactant;-   0 to 10 wt. % of water;-   0 to 50 wt. % of a cosolvent and-   a non-flammable, non-chlorine containing organic dry cleaning    solvent.

Depending on the desired cleaning, the low aqueous and non-aqueouscompositions may be used in any order. However, in some cases it will bepreferred to contact the articles with a non-aqueous composition priorto a low aqueous dry cleaning composition. In fact, the low aqueous drycleaning step may be followed or preceded with various other steps suchas a regeneration, garment care treatment and/or rinsing step, and, infact, any other step known to the person skilled in the art.

We have found that some aspects of the present invention may beespecially suitable for cleaning a laundry article stained with domesticstain material selected from the group including kitchen grease,particulate soil and mixtures thereof. Therefore, according to oneembodiment the dry cleaning process preferably comprises the step ofcontacting a laundry article with a dry cleaning composition whereby thelaundry article is stained with domestic stain material selected fromkitchen grease, particulate soil and mixtures thereof. Typicalparticulate soil stains comprises any particulate matter which iscapable of staining garments, such as dirt, mud, sand, charcoal, makeup, deodorant, toothpaste but also corroded iron particles and mixturesthereof. Kitchen grease usually comprises edible fats and oils of animalor vegetable origin such as lard, sunflower oil, soy oil, olive oil,palm oil, peanut oil, rapeseed oil and mixtures thereof.

Generally, articles such as clothing are cleaned by contacting acleaning effective amount of the dry cleaning composition according toone aspect of the invention with the articles for an effective period oftime to clean the articles or otherwise remove stains. Preferably, thelaundry article is immersed in the dry cleaning composition. The amountof dry cleaning composition used and the amount of time the compositioncontacts the article can vary based on equipment and the number ofarticles being cleaned. Normally, the dry cleaning process will compriseat least one step of contacting the article with dry cleaningcomposition according to the first aspect of the invention and at leastone step of rinsing the article with a fresh load of dry cleaningsolvent. The rinse composition will usually comprise of mainly solventbut cleaning agents may be added as desired.

We have found that the amount of dry cleaning composition used to cleana certain amount of laundry articles in a step of the dry cleaningprocess can be important. These amounts are expressed as the liquid tocloth ratio or LCR. Preferably the LCR is at most 20, more preferably atmost 10, even more preferably at most 7 and preferably greater than 0.5,more preferably greater than 0.7, even more preferably greater than 1and most preferably greater than 2.5. For the rinse step, the same LCRmay be used wherein the “liquid” refers to the rinse composition whichusually comprises only organic dry cleaning solvent with optionally somecleaning agents. When the dry cleaning process comprises differentsteps, the LCR of each step may be different or the same. Preferably,the LCR of each step is as described above.

The dry cleaning process may comprise different steps in any orderdepending on the desired outcome. The number and length of steps fore.g., cleaning, rinsing, conditioning steps may depend on the desiredoutcome. Each step may preferably last from at least 0.1 min, orpreferably at least 0.5 min or more preferably at least 1 min or even 5min, and at most 2 hrs, preferably at most 30 min, even more preferablyat most 20 min and in some instances at most 5 min. In some cases longertimes may be desired for example overnight.

Typically, each step comprises contacting the laundry article with acomposition tailored for that step, e.g. a dry cleaning composition fora cleaning step, a rinsing composition for a rinsing step, aconditioning composition for a conditioning step. Sometimes these stepsmay be combined. For example the last rinsing step may also be aconditioning step when the composition comprises conditioning agentswhile it also rinses off any unwanted residues e.g. soil or surfactants.A step will normally comprise contacting the laundry article with acomposition, agitating the laundry article in the composition, removingthe composition from the laundry article. The removal may be carried outby any means known in the art such draining, spinning or whenappropriate evaporating the composition, or any combination thereof.

The laundry articles in need of treatment are placed inside a closablevessel. It will be clear that the process is also suitable for cleaningone laundry article at the time although it will often be more efficientto clean more articles at the same time. Preferably, the vessel is arotatable drum as part of an automated dry cleaning machine that isclosed or sealed in such a way that the dry cleaning solvent can becontained within the machine if needed. Inside the vessel, the laundryarticles are then contacted with the dry cleaning composition. This maybe done in any way known in the art such as spraying or even using amist.

In some cases it may be useful to formulate the dry cleaning compositionin situ in the drum by contacting the different ingredients of the drycleaning composition separately with the laundry articles. Forexample—when the dry cleaning composition comprises dry cleaningsolvent, water and surfactant—first water, then surfactant followed bythe dry cleaning solvent. Or first the dry cleaning solvent, followed bythe surfactant and then water. Or any other order.

Alternatively, 2 or more of the ingredients may be premixed before theyare contacted with the laundry articles. For example, water andsurfactant may be premixed and this premix is then contacted with thelaundry followed by the dry cleaning solvent. In the alternate, drycleaning solvent and surfactant may be premixed and this premix is thencontacted with the laundry followed by water.

Thus, in one preferred aspect, in situ formulation of the dry cleaningcomposition may also be provided by incorporating one or moreingredients of the dry cleaning composition into a pretreatmentcomposition, pretreating the laundry articles with the pretreatmentcomposition, contacting the laundry articles with the remainingingredients of the dry cleaning composition thereby formulating the drycleaning composition in situ. This pretreatment may take place manuallyoutside the drum or mechanically inside the drum as part of apretreatment step. The pretreatment step per se need not be immersive,i.e., it may be limited to treating the stained areas only provided thatwhen the laundry articles are contacted with all the ingredients makingup the final dry cleaning composition, the laundry articles are immersedin said dry cleaning composition. For example—when the dry cleaningcomposition comprises of dry cleaning solvent, water andsurfactant—stained areas of the laundry articles may be pre-treated witha premix of water and surfactant manually or by an automated process.After effective pretreatment time is allowed, the laundry articles maybe contacted in the drum with the remaining ingredients such as in thiscase, the dry cleaning solvent (and optionally the remaining amounts ofwater and cleaning agent) to result in situ in the dry cleaningcomposition according to this aspect of the invention. The pretreatmenttime will be at least 5 sec but could be less than 1 day, preferablyless than 1 hr, more preferably less than 30 min. The pretreatmentcomposition may be formulated to treat specific stains. For examplecleaning effective amounts of protease and other enzymes may be includedto treat proteinacious stains.

In another preferred embodiment, the complete dry cleaning compositionis premixed in a separate premix compartment. For example, when the drycleaning composition comprises dry cleaning solvent, surfactant andwater, these may be premixed in a separate compartment before the drycleaning composition is contacted with the laundry article. Preferablysuch a premix is in the form of an emulsion or microemulsion. Forming apremix of for example a water-in-oil emulsion can be brought about byany number of suitable procedures. For example, the aqueous phasecontaining a cleaning effective amount of surfactant package can becontacted with the solvent phase by metered injection just prior to asuitable mixing device. Metering is preferably maintained such that thedesired solvent/water ratio remains relatively constant. Mixing devicessuch as pump assemblies or in-line static mixers, a centrifugal pump orother type of pump, a colloid mill or other type of mill, a rotarymixer, an ultrasonic mixer and other means of dispersing one liquid inanother, non-miscible liquid can be used to provide effective agitationto cause emulsification.

These static mixers are devices through which the emulsion is passed athigh speed and in which said emulsion experiences sudden changes indirection and/or in the diameter of the channels which make up theinterior of the mixers. This results in a pressure loss, which is afactor in obtaining a correct emulsion in terms of droplet size andstability.

In one variant of the method of the invention, the mixing steps are forexample sequential. The procedure consists in mixing the solvent andemulsifier in a first stage, the premix being mixed and emulsified withthe water in a second stage.

In another variant of the method of the invention, provision is made forcarrying out the above steps in a continuous mode.

The premix may take place at room temperature, which is also thetemperature of the fluids and raw materials used.

A batch process such as an overhead mixer or a continuous process suchas a two fluid co-extrusion nozzle, an in-line injector, an in-linemixer or an in-line screen can be used to make the emulsion. The size ofthe emulsion composition in the final composition can be manipulated bychanging the mixing speed, mixing time, the mixing device and theviscosity of the aqueous solution. In general, by reducing the mixingspeed, decreasing the mixing time, lowering the viscosity of the aqueoussolution or using a mixing device that produces less shear force duringmixing, one can produce an emulsion of a larger droplet size. Especiallypreferred are ultrasonic mixers. Although the description above refersto the addition of surfactant it is understood it may also apply to theaddition of cleaning agents.

While the laundry articles are in contact with the dry cleaning solvent,it is preferred to add mechanical energy for example by agitating ortumbling the laundry articles by rotating the drum or other means knownin the art. Usually after one step, the dry cleaning solvent includingany cleaning agents and/or loosened soil will be separated from thelaundry articles. This is preferably done by spinning the laundryarticles and collecting the dry cleaning composition, although otherseparation methods known in the art may also be employed such asevaporation. The dry cleaning solvent is then preferably recycled byseparating the soil and/or cleaning agents from the solvent.

In other instances it may be advantageous to recirculate at least partof the dry cleaning composition during one step. For example byseparating a portion of the dry cleaning composition from the laundryarticles, optionally filtering soil from the separated portion of drycleaning composition and contacting the laundry articles with thefiltered portion of the dry cleaning composition.

The surfactants, dry cleaning solvents, cosolvents and optional cleaningagents used in present invention are described below and may be the sameor different for each step of the inventive process.

The dry cleaning is usually performed at atmospheric pressure and roomtemperature, between 10 and 30° C. in most countries. In some instancesthe process temperature may be elevated to just under the boiling pointof the most volatile dry cleaning solvent used. Sometimes the processmay be performed under reduced or elevated pressure, typically achievedvia a vacuum pump or by supplying a gas, such as nitrogen, to theapparatus thereby increasing the pressure the closable vessel. The drycleaning process may be carried out in any suitable apparatus.Preferably, the apparatus will comprise a closable vessel and means torecycle the dry cleaning solvents used to minimise solvent losses intothe environment. The dry cleaning composition may be in the form of amicro-emulsion but usually will be in the form of a macro-emulsion,which is generally accepted to be thermodynamically unstable. A suitableprocess and appliance for dry cleaning is described in U.S. Pat. No.6,045,588. The solvent will preferably be filtered and recycled in thesame appliance. Generally, the laundry articles will be agitated in thedry cleaning process by tumbling, rotating, ultrasonics or any suitabletype of mechanical energy (see U.S. Pat. No. 6,045,588).

Still other advantages and novel features of the present invention willbecome apparent to those skilled in the art from the following detaileddescription, which presents, by way of illustration, various exemplarymodes contemplated for carrying out the invention. As will be realised,the invention is capable of other different aspects and objects allwithout departing from the invention. Accordingly, advantages, aspects,and descriptions are illustrative in nature and not restrictive.

Dry Cleaning Solvent The dry cleaning solvent is usually anon-flammable, non-chlorine containing organic dry cleaning solvent.Although the term dry cleaning solvent is used in the singular, itshould be noted that a mixture of solvents may also be used. Thus, thesingular should be taken to encompass the plural, and vice versa.Because of the typical environmental problems associated with chlorinecontaining solvents, the solvent preferably does not contain Cl atoms.In addition, the solvent should not be flammable such as most petroleumor mineral spirits having typical flash points as low as 20° C. or evenlower. The term non-flammable is intended to describe dry cleaningsolvents with a flash point of at least 37.8° C., more preferably atleast 45° C., most preferably at least 50° C. The limit of a flashpointof at least 37.8° C. for non-flammable liquids is defined in NFPA 30,the Flammable and Combustible Liquids Code as issued by National FireProtection Association, 1996 edition, Massachusetts USA. Preferred testmethods for determining the flash point of solvents are the standardtests as described in NFPA30. One preferable class of solvents is afluorinated organic dry cleaning solvent including hydrofluorocarbon(HFC) and hydrofluoroether (HFE). However, even more preferred are nonflammable non-halogenated solvents such as siloxanes(see below). Itshould be noted that mixtures of different dry cleaning solvents mayalso be used.

The most desirable solvents are non-ozone depleting and a useful commondefinition for the ozone depleting potential is defined by theEnvironmental Protection Agency in the USA: the ozone depletingpotential is the ratio of the impact on ozone of a chemical compared tothe impact of a similar mass of CFC-11. Thus, the ODP of CFC-11 isdefined to be 1.0.

Hydrofluorocarbons

One preferred hydrofluorocarbon solvent is represented by the formulaC_(x)H_(y)F_((2x+2−y)), wherein x is from 3 to 8, y is from 1 to 6, themole ratio of F/H in the hydrofluorocarbon solvent is greater than 1.6.

Preferably, x is from 4 to 6 and most preferred x is 5 and y is 2.

Especially suitable are hydrofluorocarbon solvents selected from isomersof decafluoropentane and mixtures thereof. In particular useful is1,1,1,2,2,3,4,5,5,5-decafluoropentane. The E.I. Du Pont De Nemours andCompany markets this compound under the name Vertrel XF™.

Hydrofluoroethers

Hydrofluoroethers (HFEs) suitable for use in the present invention aregenerally low polarity chemical compounds minimally containing carbon,fluorine, hydrogen, and catenary (that is, in-chain) oxygen atoms. HFEscan optionally contain additional catenary heteroatoms, such as nitrogenand sulphur. HFEs have molecular structures which can be linear,branched, or cyclic, or a combination thereof (such asalkylcycloaliphatic), and are preferably free of ethylenic unsaturation,having a total of about 4 to about 20 carbon atoms. Such HFEs are knownand are readily available, either as essentially pure compounds or asmixtures.

Preferred hydrofluoroethers can have a boiling point in the range fromabout 40° C. to about 275° C., preferably from about 50° C. to about200° C., even more preferably from about 50° C. to about 121° C. It isvery desirable that the hydrofluoroether has no flashpoint. In general,when a HFE has a flash point, decreasing the F/H ratio or decreasing thenumber of carbon-carbon bonds each decreases the flash point of the HFE(see WO/00 26206).

Useful hydrofluoroethers include two varieties: segregatedhydrofluoroethers and omega-hydrofluoroalkylethers. Structurally, thesegregated hydrofluoroethers comprise at least one mono-, di-, ortrialkoxy-substituted perfluoroalkane, perfluorocycloalkane,perfluorocycloalkyl-containing perfluoroalkane, orperfluorocycloalkylene-containing perfluoroalkane compound.

HFEs suitable for use in the processes of the invention include thefollowing compounds:

-   C₄F₉OC₂F₄H-   HC₃F₆OC₃F₆H-   HC₃F₆OCH₃-   C₅F₁₁OC₂F₄H-   C₆F₁₃OCF₂H-   C₆F₁₃OC₂F₄OC₂F₄H-   c-C₆F₁₁CF₂OCF₂H-   C₃F₇OCH₂F-   HCF₂O(C₂F₄O)_(n)(CF₂O)_(m)CF₂H, wherein m=0 to 2 and n=0 to 3-   C₃F₇O[C(CF₃)₂CF₂O]_(p)CFHCF₃, wherein p=0 to 5-   C₄F₉OCF₂C (CF₃)₂CF₂H-   HCF₂CF₂OCF₂C (CF₃)₂CF₂OC₂F₄H-   C₇F₁₅OCFHCF₃-   C₈F₁₇OCF₂O(CF₂)₅H-   C₈F₁₇OC₂F₄OC₂F₄OC₂F₄OCF₂H-   C₄F₉OC₂H₅-   C₄F₉OCH₃-   C₈F₁₇OCH₃

Preferred HFEs are according to the formulaC_(n)X_(2n+1)—O—C_(m)Y_(2m+1)Wherein X and Y are each independently F or H provided that at least oneF is present. Preferably, X=F and Y=H; n=2-15 and m=1-10, butpreferably, n=3-8 and m=1-4, or more preferably n=4-6 and m=1-3.

Especially preferred is a HFE wherein n=4 and m=1 or 2 which is marketedunder the name of HFE 7100™ and 7200™ respectively by the 3Mcorporation.

Mixtures of different organic dry cleaning solvents may also be used.For example, a suitable dry cleaning composition may comprise a mixtureof at least one HFE together with at least one siloxane.

When solvent compounds are mentioned, isomers thereof are also included.Thus, suitable HFEs include nonafluoromethoxybutane (C4F9OCH3) isomerssuch as 1,1,1,2,2,3,3,4,4-nonafluoro-4-methoxy-butane(CH3OCF2CF2CF2CF3),1,1,1,2,3,3-hexafluoro-2-(trifluoromethyl)-3-methoxy-propane(CH3OCF2CF(CF3)2),1,1,1,3,3,3-hexafluoro-2-methoxy-2-(trifluoromethyl)-propane(CH3OC(CF3)3), and 1,1,1,2,3,3,4,4,4-nonafluoro-2-methoxy-butane(CH3OCF(CF3)CF2CF3), approximate isomer boiling point 60° C.; Alsoisomers of nonafluoroethoxybutane (C4F9OC2H5) such as1,1,1,2,2,3,3,4,4-nonafluoro-4-ethoxybutane (CH3CH2OCF2CF2CF2CF3),1,1,1,2,3,3-hexafluoro-2-(trifluoromethyl)-3-ethoxypropane(CH3CH2OCF2CF(CF3)2),1,1,1,3,3,3-hexafluoro-2-ethoxy-2-(trifluoromethyl)-propane(CH3CH2OC(CF3)3), and 1,1,1,2,3,3,4,4,4-nonafluoro-2-ethoxybutane(CH3CH2OCF(CF3)CF2CF3) with approximate isomer boiling points of 73° C.

Siloxane Dry Cleaning Solvent

Some siloxane solvents may also be used advantageously in the presentinvention. The siloxane may be linear, branched, cyclic, or acombination thereof. One preferred branched siloxane is tris(trimethylsiloxyl) silane. Also preferred are linear and cyclic oligodimethylsiloxanes. One preferred class of siloxane solvents is analkylsiloxane represented by the formulaR₃—Si(—O—SiR₂)_(w)—R

Where each R is independently chosen from an alkyl group having form 1to 10 carbon atoms and w is an integer from 1 to 30. Preferably, R ismethyl and w is 1-4 or even more preferably w is 3 or 4.

Of the cyclic siloxane octamethyl cyclotetrasiloxane and decamethylcyclopentasiloxane are particularly effective.

Very useful siloxanes are selected from the group consisting ofdecamethyl tetrasiloxane, dodecamethyl pentasiloxane and mixturesthereof.

Preferably, the organic dry cleaning solvent is not a terpene.

Especially suitable organic dry cleaning solvents include those selectedfrom the group consisting of the isomers of nonafluoromethoxybutane,nonafluoroethoxybutane and decafluoropentane, octamethylcyclotetrasiloxane, decamethyl cyclopentasiloxane, decamethyltetrasiloxane, dodecamethyl pentasiloxane and mixtures thereof. Evenmore preferred organic dry cleaning solvents include those selected fromthe group consisting of octamethyl cyclotetrasiloxane, decamethylcyclopentasiloxane, decamethyl tetrasiloxane, dodecamethyl pentasiloxaneand mixtures thereof.

The dry cleaning compositions of the invention generally contain greaterthan about 50 percent by weight of organic dry cleaning solvent,preferably greater than about 75 weight percent, more preferably greaterthan about 80 weight percent, more preferably greater than about 85weight percent, even more preferably greater than about 95 weightpercent, but preferably less than 100 weight percent of organic drycleaning solvent by weight of the total dry cleaning composition. Suchamounts aid in improved drying times and maintain a high flashpoint orno flashpoint at all. For the rinse step or conditioning step the drycleaning compositions may even comprise of at least 99 weight percent oforganic dry cleaning solvent by weight of the total dry cleaningcomposition and sometimes even 100 weight percent of organic drycleaning solvent.

Water

In some cases water may be used in the dry cleaning process and theamount of water is important. In those cases, the amount of waterpresent in any step of the dry cleaning process is at such a level thatlaundry articles can be safely cleaned. This includes laundry articlesthat can only be dry cleaned. The amount of water present in the lowaqueous dry cleaning composition is preferably from 0.01 to 50 wt. %water more preferably from 0.01 to 10 wt. %, even more preferably from0.01 to 0.9 wt. % water by weight of the dry cleaning composition ormore preferably, 0.05 to 0.8 wt. % or most preferable 0.1 to 0.7 wt. %.The amount of water present in the non-aqueous dry cleaning compositionis preferably from 0 to 0.1 wt. % water by weight of the dry cleaningcomposition or more preferably, 0 to 0.01 wt. % or even more preferable0 to 0.001 wt. % and most preferable 0 wt. %. When the dry cleaningcomposition comprises water, preferably the water to cloth ratio (w/w)(WCR) is less than 0.45, more preferably less than 0.35, more preferablyless than 0.25, more preferably less than 0.2, most preferably less than0.15, but usually more than 0.0001, preferably more than 0.001, morepreferably more than 0.01.

When the dry cleaning process comprises more than one step, this WCRpreferably applies to all steps in the dry cleaning process, especiallywhen the dry cleaning composition comprises water and solvent. However,the WCR may or may not differ for each step. It is also preferred thatthis WCR applies to each steps in the dry cleaning process wherein theLCR is more than 1.

Cosolvents

The compositions of the invention may contain one or more cosolvents.The purpose of a cosolvent in the dry cleaning compositions of theinvention is often to increase the solvency of the dry cleaningcomposition for a variety of soils. The cosolvent also enables theformation of a homogeneous solution containing a cosolvent, a drycleaning solvent, and the soil; or a cosolvent, a dry cleaning solventand an optional cleaning agent. As used herein, a “homogeneouscomposition” is a single phased composition or a composition thatappears to have only a single phase, for example, a macro-emulsion, amicro-emulsion or an azeotrope. However, if a cosolvent is used the drycleaning composition is preferably a non-azeotrope as azeotropes may beless robust.

Useful cosolvents of the invention are soluble in the dry cleaningsolvent or water, are compatible with typical cleaning agents, and canenhance the solubilisation of hydrophilic composite stains and oilstypically found in stains on clothing, such as vegetable, mineral, oranimal oils. Any cosolvent or mixtures of cosolvents meeting the abovecriteria may be used.

Useful cosolvents include alcohols, ethers, glycol ethers, alkanes,alkenes, linear and cyclic amides, perfluorinated tertiary amines,perfluoroethers, cycloalkanes, esters, ketones, aromatics, the fully orpartly halogenated derivatives thereof and mixtures thereof. Preferably,the cosolvent is selected from the group consisting of alcohols,alkanes, alkenes, cycloalkanes, ethers, esters, cyclic amides,aromatics, ketones, the fully or partly halogenated derivatives thereofand mixtures thereof.

Representative examples of cosolvents which can be used in the drycleaning compositions of the invention include methanol, ethanol,isopropanol, t-butyl alcohol, trifluoroethanol, pentafluoropropanol,hexafluoro-2-propanol, methyl t-butyl ether, methyl t-amyl ether,propylene glycol n-propyl ether, propylene glycol n-butyl ether,dipropylene glycol n-butyl ether, propylene glycol methyl ether,ethylene glycol monobutyl ether, trans-1,2-dichloroethylene, decalin,methyl decanoate, t-butyl acetate, ethyl acetate, glycol methyl etheracetate, ethyl lactate, diethyl phthalate, 2-butanone, N-alkylpyrrolidone (such as N-methyl pyrrolidone, N-ethyl pyrrolidone), methylisobutyl ketone, naphthalene, toluene, trifluorotoluene,perfluorohexane, perfluoroheptane, perfluorooctane,perfluorotributylamine, perfluoro-2-butyl oxacyclopentane.

Preferably, the cosolvent is present in the compositions of theinvention in an effective amount by weight to form a homogeneouscomposition with the other dry cleaning solvent(s) such as HFE. Theeffective amount of cosolvent will vary depending upon which cosolventor cosolvent blends are used and the other dry cleaning solvent(s) usedin the composition. However, the preferred maximum amount of anyparticular cosolvent present in a dry cleaning composition should be lowenough to keep the dry cleaning composition non-flammable as definedabove.

In general, cosolvent may be present in the compositions of theinvention in an amount of from about 1 to 50 percent by weight,preferably from about 5 to about 40 percent by weight, and morepreferably from about 10 to about 25 percent by weight. In someexceptional cases the cosolvent may be present amounts of from about0.01 percent by weight of the total dry cleaning composition.

Surfactants

The dry cleaning compositions of the invention can utilise many types ofcyclic, linear or branched surfactants known in the art, bothfluorinated and non-fluorinated. Preferred solvent compatiblesurfactants include nonionic, anionic, cationic and zwitterionicsurfactants having at least 4 carbon atoms, but preferably less than 200carbon atoms or more preferably less than 90 carbon atoms as describedbelow. Solvent compatible surfactants usually have a solvent-philic partthat increases the solubility of the surfactant in the dry cleaningsolvent/composition. Effective surfactants may comprise of one or morepolar hydrophilic groups and one or more dry cleaning solvent-philicparts having at least 4 carbon atoms so that the surfactant is solublein said dry cleaning solvent/composition. It is preferred that thesurfactant is soluble in the dry cleaning composition, i.e., to at leastthe amount of surfactant used in the dry cleaning composition at 20° C.The composition may comprise one or a mixture of surfactants dependingon the desired cleaning and garment care. One preferred surfactant is ananionic surfactant. Another preferred surfactant is a cationicsurfactant.

The polar hydrophilic group, Z, can be nonionic, ionic (that is,anionic, cationic, or amphoteric), or a combination thereof. Typicalnonionic moieties include polyoxyethylene and polyoxypropylene moieties.Typical anionic moieties include carboxylate, sulfonate, sulfate, orphosphate moieties. Typical cationic moieties include quaternaryammonium, protonated ammonium, imidazolines, amines, diamines,sulfonium, and phosphonium moieties. Typical amphoteric moieties includebetaine, sulfobetaine, aminocarboxyl, amine oxide, and various othercombinations of anionic and cationic moieties. Especially suitablesurfactants comprise at least one polar hydrophilic group Z which is ananionic moiety whereby the counterion may be as described below.

The polar hydrophilic group Z is preferably selected from the groupcomprising —SO₄M, —SO₃M, —PO₄M₂, —PO₃M₂, —CO₂M and mixtures thereofwherein each M can be independently selected from the group including H,NR₄, Na, K and Li, wherein each R is independently selected from H andC₁₋₄ alkyl radical but preferably H. Preferably M is H but in some casessalts may also be used.

Fluorinated Surfactants

In one preferred embodiment, the surfactant is fluorinated or morepreferably a fluorinated acid.

Suitable fluorosurfactants are in most cases those according to theformula (I):(Xf)_(n)(Y)_(m)(Z)_(p)  (I)and contain one, two or more fluorinated radicals (Xf) and one or morepolar hydrophilic groups (Z), which radicals and polar hydrophilicgroups are usually (but not necessarily) connected together by one ormore suitable linking groups (Y). Preferably, n and p are integersindependently selected from 1 to 4 and m is selected from 0 to 4. Whenthe surfactant comprises more than one Xf, Y or Z group, then each ofXf, Y and Z may be the same or different. Preferably, the polarhydrophilic group is connected by a covalent bond to Y, or in absence ofY, to Xf.

The fluorinated radical, Xf, can generally be a linear or cyclic,saturated or unsaturated, aromatic or non-aromatic, radical preferablyhaving at least 3 carbon atoms. The carbon chain may be linear orbranched and may include hetero atoms such as oxygen or sulphur, butpreferably not nitrogen. Preferably, Xf is an aliphatic and saturated. Afully fluorinated Xf radical is preferred, but hydrogen or chlorine maybe present as substituents provided that not more than one atom ofeither is present for every two carbon atoms, and, preferably, theradical contains at least a terminal perfluoromethyl group. Radicalscontaining no more than about 20 carbon atoms are preferred becauselarger radicals usually represent a less efficient utilisation offluorine.

Especially suitable Xf groups can be based on perfluorinated carbon:C_(n)F_(2n+1)—wherein n is from 1-40, preferably 2 to 26, mostpreferably 2 to 18 or can be based on oligomers ofhexafluoropropyleneoxide: [CF(CF₃)—CF₂—O]_(n) wherein n is from 1 to 30.Suitable examples of the latter are marketed by E.I DuPont de Nemoursand Co. under the name Krytoxl 157, especially, Krytoxl 157 FSL.Fluoroaliphatic radicals containing about 2 to 14 carbon atoms are morepreferred.

The linking group, Y, is selected from groups such as alkyl, alkylene,alkylene oxide, arylene, carbonyl, ester, amide, ether oxygen, secondaryor tertiary amine, sulfonamidoalkylene, carboxamidoalkylene,alkylenesulfonamidoalkylene, alkyleneoxyalkylene, oralkylenethioalkylene or mixtures thereof. In one preferred embodiment Yis (CH₂)_(t) or (CH₂)_(t)O wherein t is 1 to 10, preferably 1 to 6, mostpreferably 2 to 4. Alternatively, Y may be absent, in which case Xf andZ are directly connected by a covalent bond.

A particularly useful class of fluoroaliphatic surfactants useful inthis invention are those wherein Xf, Y, and Z are as defined, and n is 1or 2, m is 0 to 2, and p is 1 or 2.

Examples of very useful surfactants are those comprising at leastwherein n is 1 to 4, m is 0 to 4, and p is 1 to 4, Z is as defined and

-   Xf=R¹-   Y=(R²)_(v)    wherein R¹ is a perfluoroalkyl group having 1 to 40 carbon atoms; R²    is an alkyl or an alkylene oxide group having 2 to 6 carbon atoms;    and v is 0-10

Preferably, the surfactant is according to the formula[R¹—R² _(v)]_(w)PO(OH)_(3−w)wherein R¹ is a perfluoroalkyl group having 1 to 26 carbon atoms; R² isan alkyl or an alkylene oxide group having 2 to 6 carbon atoms; v is0-10 and w is 1-2.

More preferably, R¹ is a perfluoroalkyl group having 2 to 16 carbonatoms; R² is an alkyl or an alkylene oxide group having 2 to 6 carbonatoms; v is 1 and w is 1 or 2.

Most preferably, R¹ is a perfluoroalkyl group having 2 to 14 carbonatoms; R² is ethylene oxide; v=1 and w=1-2.

Non-Fluorinated Surfactant

One other suitable class of surfactants are non-fluorinated surfactantsaccording the formula (II):(Xh)_(n)(Y)_(m)(Z)_(p)  (II)wherein Xh is a non-fluorinated radical and(Y), (Z), n, m and p are asdescribed above for formula (I).

Xh may be a linear, branched or cyclic, saturated or unsaturated,aromatic or non-aromatic, radical preferably having at least 4 carbonatoms. Xh preferably includes hydrocarbon radicals. When Xh is ahydrocarbon, the carbon chain may be linear, branched or cyclic and mayinclude hetero atoms such as oxygen, nitrogen or sulphur, although insome cases nitrogen is not preferred. Preferably, Xh is aliphatic andsaturated. Radicals containing no more than about 24 carbon atoms arepreferred. One preferred surfactant is an acid surfactant. Preferredsurfactants include anionic surfactants. Anionic surfactants aregenerally known in the art and include, for example, alkyl arylsulfonates (such as, for example, alkylbenzenesulfonates), alkyl arylsulfonic acids (such as, for example, sodium and ammonium salts oftoluene-, xylene- and isopropylbenzenesulfonic acids), sulfonated aminesand sulfonated amides (such as, for example, amidosulfonates),carboxylated alcohols and carboxylated alkylphenol ethoxylates, diphenylsulfonates, fatty esters, isethionates, lignin-based surfactants, olefinsulfonates (such as, for example, RCH—CHSO₃Na, where R is C₁₀-C₁₆),phosphorous-based surfactants, protein based surfactants,sarcosine-based surfactants (such as, for example, N-acylsarcosinatessuch as sodium N-lauroylsarcosinate), sulfates and sulfonates of oilsand/or fatty acids, sulfates and sulfonates of ethoxylated alkylphenols,sulfates of alcohols, sulfates of ethoxylated alcohols, sulfates offatty esters, sulfates of aromatic or fluoro containing compounds,sulfosuccinnamates, sulfosuccinates (such as, for example, diamyl-,dioctyl- and diisobutylsulfosuccinates), taurates, and sulfonic acids.Examples of suitable non-fluorinated anionic surfactants includeCrodafos™ 810A (ex Croda).

In addition to an acid surfactant other classes of surfactants may beused. Suitable surfactants include, but are not limited to nonionic andcationic surfactants. Compounds suitable for use as the nonionicsurfactant of the present invention are those that carry no discretecharge when dissolved in aqueous media. Nonionic surfactants aregenerally known in the art and include, for example, alkanol amides(such as, for example, coco, lauric, oleic and stearicmonoethanolamides, diethanolamides and monoisopropanolamides), amineoxides (such as, for example, polyoxyethylene ethanolamides andpolyoxyethylene propanolamides), polyalkylene oxide block copolymers(such as, for example, poly(oxyethylene-cooxypropylene)), ethoxylatedalcohols, (such as, for example, isostearyl polyoxyethylene alcohol,lauryl, cetyl, stearyl, oleyl, tridecyl, trimethylnonyl, isodecyl,tridecyl), ethoxylated alkylphenols (such as, for example,fionylphenol), ethoxylated amines and ethoxylated amides, ethoxylatedfatty acids, ethoxylated fatty esters and ethoxylated fatty oils (suchas, for example, mono- and diesters of acids such as lauric, isostearic,pelargonic, oleic, coco, stearic, and ricinoleic, and oils such ascastor oil and tall oil), fatty esters, fluorocarbon containingmaterials, glycerol esters (such as, for example, glycerol monostearate,glycerol monolaurate, glycerol dilaurate, glycerol monoricinoleate, andglycerol oleate), glycol esters (such as, for example, propylene glycolmonostearate, ethylene glycol monostearate, ethylene glycol distearate,diethylene glycol monolaurate, diethylene glycol monolaurate, diethyleneglycol monooleate, and diethylene glycol stearate), lanolin-basedsurfactants, monoglycerides, phosphate esters, polysaccharide ethers,propoxylated fatty acids, propoxylated alcohols, and propoxylatedalkylphenols, protein-based organic surfactants, sorbitan-basedsurfactants (such as, for example, sorbitan oleate, sorbitanmonolaurate, and sorbitan palmitate), sucrose esters and glucose esters,and thio- and mercapto-based surfactants.

In a preferred embodiment, one component of the present inventioncomprises one or more nonionic surfactants according to one or more ofthe structural formulas III and IV:R⁹—O—(CH₂—CH₂—O)_(n)—R¹⁰  (III)R⁹—O—(CH₂—C(CH₃)H—O)_(n)—R¹⁰  (IV)wherein:

-   R⁹ is a monovalent hydrocarbon group of from 1 to 30 carbons that    may be linear, cyclic, branched, unsaturated, aromatic or fluoro    containing; R¹⁰ is hydrogen or a monovalent hydrocarbon group of 1    to 30 carbons that may be linear, cyclic, branched, unsaturated,    aromatic or fluoro containing; and n is from about 1 to about 100,    more preferably from about 1 to about 40. In a highly preferred    embodiment, R⁹ contains from 2 to about 24 carbons, even more    preferably from 8 to 24 carbons, R¹⁰ is H and n is from about 2 to    about 20.

Other suitable nonionic surfactants include Polyethylene oxidecondensates of nonyl phenol and myristyl alcohol, such as in U.S. Pat.No. 4,685,930 Kasprzak; and b) fatty alcohol ethoxylates,R—(OCH₂CH₂)_(a)OH wherein a=1 to 100, typically 1 to 30, R=hydrocarbonresidue 8 to 20 C atoms, typically linear alkyl. Examplespolyoxyethylene lauryl ether, with 4 or 10 oxyethylene groups;polyoxyethylene cetyl ether with 2, 6 or 10 oxyethylene groups;polyoxyethylene stearyl ether, with 2, 5, 15, 20, 25 or 100 oxyethylenegroups; polyoxyethylene (2), (10) oleyl ether, with 2 or 10 oxyethylenegroups. Commercially available examples include, but are not limited to:BRIJ and NEODOL. See also U.S. Pat. No. 6,013,683 Hill et al. Othersuitable nonionic surfactants include Tween™.

Suitable cationic surfactants include, but are not limited todialkyldimethyl ammonium salts having the formula: R′R″N⁺(CH₃)₂X⁻wherein R′ and R″ are each independently selected from the groupconsisting of hydrocarbon containing moiety containing 1-30 C atoms orderived from tallow, coconut oil or soy, X=Cl, I or Br. Examplesinclude: didodecyldimethyl ammonium bromide (DDAB), dihexadecyldimethylammonium chloride, dihexadecyldimethyl ammonium bromide,dioctadecyldimethyl ammonium chloride, dieicosyldimethyl ammoniumchloride, didocosyldimethyl ammonium chloride, dicoconutdimethylammonium chloride, ditallowdimethyl ammonium bromide (DTAB).Commercially available examples include, but are not limited to: ADOGEN,ARQUAD, TOMAH, VARIQUAT. See also U.S. Pat. No. 6,013,683 Hill et al.

Also suitable surfactants are silicone surfactants including, but notlimited to the polyalkyleneoxide polydimethylsiloxanes having apolydimethylsiloxane hydrophobic moiety and one or more hydrophilicpolyalkyleneoxide side chains and have the general formula:R¹—(CH₃)₂SiO—[(CH₃)₂SiO]_(a)—[(CH₃)(R¹)SiO]_(b)—Si(CH₃)₂—R¹wherein a+b are from about 1 to about 50, preferably from about 3 toabout 30, more preferably from about 10 to about 25, and each R¹ is thesame or different and is selected from the group consisting of methyland a poly(ethyleneoxide/propyleneoxide) copolymer group having thegeneral formula: —(CH₂)_(n)O(C₂H₄O)_(c)(C₃H₆O)_(d)R² with at least oneR¹ being a poly(ethyleneoxide/propyleneoxide) copolymer group, andwherein n is 3 or 4, preferably 3; total c (for all polyalkyleneoxideside groups) has a value of from 0 to about 100, preferably from about 6to about 100; total d is from 0 to about 14, preferably from 0 to about3; and more preferably d is 0; total c+d has a value of from about 5 toabout 150, preferably from about 9 to about 100 and each R² is the sameor different and is selected from the group consisting of hydrogen, analkyl having 1 to 4 carbon atoms, and an acetyl group, preferablyhydrogen and methyl group. Examples of these surfactants may be found inU.S. Pat. No. 5,705,562 and U.S. Pat. No. 5,707,613, both of which areincorporated herein by reference.

Examples of this type of surfactants are the Silwet™ surfactants whichare available from CK Witco, OSi Division, Danbury, Conn. RepresentativeSilwet™ surfactants are for example L-7608, L-7607, L-77, L-7605,L-7604, L-7600, L-7657, L-7602. The molecular weight of thepolyalkyleneoxide group (R¹) is less than or equal to about 10,000.Preferably, the molecular weight of the polyalkyleneoxide group is lessthan or equal to about 8,000, and most preferably ranges from about 300to about 5,000. Thus, the values of c and d can be those numbers whichprovide molecular weights within these ranges. However, the number ofethyleneoxide units (—C₂H₄O) in the polyether chain (R¹) must besufficient to render the polyalkyleneoxide polysiloxane waterdispersible or water soluble. If propyleneoxide groups are present inthe polyalkyleneoxide chain, they can be distributed randomly in thechain or exist as blocks. Especially preferred Silwet™ surfactants areL-7600, L-7602, L-7604, L-7605, L-7657, and mixtures thereof. Besidescleaning and/or emulsifying activity, polyalkyleneoxidepolydimethylsiloxane surfactants can also provide other benefits, suchas anti-static benefits, and softness to fabrics.

The preparation of polyalkyleneoxide polydimetylsiloxanes is well knownin the art. Polyalkyleneoxide polydimethylsiloxanes of the presentinvention can be prepared according to the procedure set forth in U.S.Pat. No. 3,299,112, incorporated herein by reference.

Another suitable silicone surfactant is SF-1488, which is available fromGE silicone fluids. Especially preferred silicone surfactants includeTegopren™ 7008 and 7009 (ex Goldschmidt).

These and other surfactants suitable for use in combination with theorganic dry cleaning solvent as adjuncts are well known in the art,being described in more detail in Kirk Othmer's Encyclopaedia ofChemical Technology, 3rd Ed., Vol. 22, pp. 360-379, “Surfactants andDetersive Systems”, incorporated by reference herein. Further suitablenonionic detergent surfactants are generally disclosed in U.S. Pat. No.3,929,678, Laughlin et al., issued Dec. 30, 1975, at column 13, line 14through column 16, line 6, incorporated herein by reference. Othersuitable detergent surfactants are generally disclosed in WO-A-0246517.

The surfactant or mixture of surfactants is present in a cleaningeffective amount. A cleaning effective amount is the amount needed forthe desired cleaning. This will, for example, depend on the number ofarticles, level of soiling and volume of dry cleaning composition used.However, surprisingly effective cleaning was observed when thesurfactant was present from at least 0.001 wt. % to 10 wt. % by weightof the dry cleaning composition. More preferably, the surfactant ispresent from 0.01 to 3 wt. % or even more preferably from 0.05 to 0.9wt. % by weight of the dry cleaning composition. More preferably, thesurfactant is present from 0.1 to 0.8 wt. % or even more preferably from0.3 to 0.7 wt. % by weight of the dry cleaning composition.

Surprisingly, it was found that the surfactant to cloth ratio (w/w)(SCR) was important in many cases to obtain an effective cleaning whilemaintaining a good garment care. Preferably, the SCR is at most 0.25,more preferably at most 0.12, more preferably at most 0.08, morepreferably at most 0.04, but preferably at least 0.0001, more preferablyat least 0.0003, more preferably at least 0.001 and most preferably atleast 0.002.

Optional Cleaning Agents

The dry cleaning compositions may contain one or more optional cleaningagents. Cleaning agents include any agent suitable for enhancing thecleaning, appearance, condition and/or garment care. Generally, thecleaning agent may be present in the compositions of the invention in anamount of about 0 to 20 wt. %, preferably 0.001 wt. % to 10 wt. %, morepreferably 0.01 wt. % to 2 wt. % by weight of the total dry cleaningcomposition.

Some suitable cleaning agents include, but are not limited to, builders,enzymes, bleach activators, bleach catalysts, bleach boosters, bleaches,alkalinity sources, antibacterial agents, colorants, perfumes,pro-perfumes, finishing aids, lime soap dispersants, compositionmalodour control agents, odour neutralisers, polymeric dye transferinhibiting agents, crystal growth inhibitors, photobleaches, heavy metalion sequestrants, anti-tarnishing agents, anti-microbial agents,anti-oxidants, anti-redeposition agents, soil release polymers,electrolytes, pH modifiers, thickeners, abrasives, divalent or trivalentions, metal ion salts, enzyme stabilisers, corrosion inhibitors,diamines or polyamines and/or their alkoxylates, suds stabilisingpolymers, process aids, fabric softening agents, optical brighteners,hydrotropes, suds or foam suppressors, suds or foam boosters, fabricsofteners, anti-static agents, dye fixatives, dye abrasion inhibitors,anti-crocking agents, wrinkle reduction agents, wrinkle resistanceagents, soil repellency agents, sunscreen agents, anti-fade agents, andmixtures thereof.

The invention is more fully illustrated by the following non-limitingexamples showing some preferred embodiments of the invention.

EXAMPLES

Laundry articles are contacted with the following low aqueous drycleaning compositions A (see table I) and agitated for 15 minutes at 20°C. using a liquid to cloth ratio of 13. Subsequently, the dry cleaningcomposition is removed and the laundry articles are rinsed with a rinsecomposition comprising clean dry cleaning solvent. The experiment isrepeated with following low aqueous dry cleaning compositions B-F (seetable I) using an liquid to cloth ratio of 5. TABLE I Composition A B CD E F Surfactant Zonyl UR ™ 0.5 (wt. %) Krytox ™ 0.1 157 FSL Crodafos ™0.1 0.5 0.1 0.5 810A (ex Croda) Water — 0.25 0.5 0.5 1.0 1.0 Solvent(Balance) HFE-7200 ™ x x Dodecamethyl x pentasiloxane Decamethyl xtetrasiloxane Decamethyl x x cyclopentasiloxane

Zonyl™ UR fluorosurfactant is available from E.I DuPont de Nemours andCo. Nonafluoromethoxybutane is marketed under the name HFE-7100™ by the3M Company.

1. A dry cleaning process for in-home dry cleaning comprising a drycleaning step of contacting a laundry article stained with particulatesoil with a dry cleaning composition wherein the liquor to cloth ratio(w/w) (LCR) is at most 20, and wherein said composition comprises a) anon-flammable, non-chlorine containing organic dry cleaning solvent; b)from 0.05 to 0.9% by weight of an acid surfactant.
 2. A dry cleaningprocess for in-home dry cleaning according to claim 1 wherein the drycleaning step is a low aqueous dry cleaning step and said composition isa low aqueous dry cleaning composition comprising 0.01 to 10 wt. % ofwater.
 3. A dry cleaning process for in-home dry cleaning according toclaim 2 wherein the low aqueous dry cleaning composition comprises from0.01 to 0.8 wt. % of an acid surfactant by weight of the total drycleaning composition.
 4. A dry cleaning process for in-home dry cleaningaccording to claim 1 whereby said liquid to cloth ratio (w/w) is at most10.
 5. A dry cleaning process for in-home dry cleaning according toclaim 1 whereby the dry cleaning composition is a low aqueous drycleaning composition and comprises 0.01 to 10 wt. % of water andpreferably the water to cloth ratio (w/w) during the low aqueous drycleaning step is less than 0.45, preferably less than 0.2.
 6. A drycleaning process for in-home dry cleaning according to claim 1 whereinthe process further comprises a non-aqueous dry cleaning step whereinthe laundry article contacted with a non-aqueous dry cleaningcomposition, said non-aqueous dry cleaning composition comprising 0.001to 10 wt. % of a surfactant; 0 to 0.01 wt. % of water; 0 to 50 wt. % ofa cosolvent and a non-flammable, non-chlorine containing organic drycleaning solvent.
 7. A dry cleaning process for in-home dry cleaningaccording to claim 6 wherein the non-aqueous dry cleaning step precedesthe low-aqueous dry cleaning step.
 8. A dry cleaning process accordingto claim 1 wherein the non-flammable, non-chlorine containing organicdry cleaning solvent is selected from the group consisting of theisomers of nonafluoromethoxybutane, nonafluoroethoxybutane anddecafluoropentane, octamethyl cyclotetrasiloxane, decamethylcyclopentasiloxane, decamethyl tetrasiloxane, dodecamethyl pentasiloxaneand mixtures thereof.
 9. A dry cleaning process for in-home dry cleaningaccording to claim 5 wherein said WCR applies to all steps in the drycleaning process wherein the LCR is more than 1.